<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <title>CSS3 开关，3选2</title>
    <link rel="stylesheet" href="3/normalize.min.css">
    <link rel="stylesheet" href="3/style.css">
</head>

<body>
    <div id="app"></div>
    <script src='3/react.development.js'></script>
    <script src='3/react-dom.development.js'></script>
    <script src='3/prop-types.min.js'></script>
    <script src="3/index.js"></script>
</body>

</html>